1. Field of the Invention
The present invention relates to a keysensor having an insertion hole for a keyholder.
2. Description of the Related Art
Keysensors having an insertion hole for a keyholder have been conventionally used at places like hotels, etc. The signals showing "Occupied" when the plate-shaped keyholder is inserted in the hole of the keysensor, or "vacant" when the keyholder is removed from the hole, are generated and sent to a display unit at a front desk of a hotel, etc. People at the front desk, then know whether each customer is in the room or not, and may selectively turn on or off the switch to the room.
The conventional keysensors are designed only for the above-mentioned use, thus, they have a single switch which senses whether the keyholder is inserted or not. Specifically, a metal sheet, such as iron, is contained by the keyholder and a magnet and a reed switch are oppositely placed across an insertion hole in the keysensor. The reed switch is closed when the keyholder is removed, and is opened when the keyholder is inserted. In the configuration mentioned above, the position of the switch remains unchanged if the same keyholder is reversely inserted.
At places like hotels, etc., employees usually clean the room and check the facilities after the room is vacated. Attendants at the front desk need to know whether a room is being cleaned or has been cleaned or the room is occupied or vacated, and so far they relied on the telephone only.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims.